ABSTRACT
Mechanical ventilation is becoming more and more common in clinical practice.It certainly helps patients to overcome the respiratory failure in children, but in the meantime, also lead to ventilator-induced diaphragm dysfunction(VIDD). VIDD is common in mechanical ventilation patients and are associated with prolonged duration of mechanical ventilation, difficult weaning, pulmonary infection and the mortality.With the development of clinical medical technology, more and more convenient devices are applied to monitor diaphragm function.This review expounded the latest monitoring technology and assessment indices of VIDD, including pressure-generating capacity, imaging examination and diaphragm electrical activity.
ABSTRACT
Objective:To investigate the protective effect of external diaphragm pacing on the prevention of ventilator-induced diaphragm dysfunction (VIDD) in rabbits and its mechanism.Methods:Eighty-five New Zealand white rabbits were randomly (random number) divided into the blank control group (BC, n=5), spontaneous breathing group (SB, n=20), volume control ventilation group (VC, n=20), external diaphragm pacing group (EDP, n=20), external diaphragm pacing and volume control ventilation group (EDP+ VC, n=20). After successful modeling, the rabbits in each group were treated accordingly except for the BC group. Rabbitss in the BC group were not mechanically ventilated, and the diaphragm was removed immediately after anesthetizing. Whole diaphragms of 5 rabbits per time point per other group were also collected after anesthesia at post treatment hour (PTH) 6 and on post treatment day (PTD) 1, 3, and 7. Diaphragm weight/body weight and diaphragm isometric contractile force of each group were measured. The pathological changes of diaphragmatic tissues were observed by HE staining. The protein expressions of Cyt c, RyR1, caspase-3, and p-mTORC1 were measured by Western blot. Repeated measures analysis of variance was used for the comparison between multiple groups of variables at different time points, and LSD- t test was used for the further comparison between two groups at the same time point, a P<0.05 was considered statistically significant. Results:Compared with the BC group, the VC group showed diaphragmatic pathological changes conformed to VIDD: DW/BW was decreased obviously; HE staining revealed obvious changes in diaphragmatic tissue; Diaphragmatic contractility was also significantly decreased; The expression of Cyt c and caspase-3 were increased while the expression of RyR1 and p-mTORC1 were decreased gradually with the extension of treatment time ( P<0.05). Compared the EDP+VC group with the VC group, with the extension of treatment time, DW, DW/BW, pathological damages and diaphragmatic contractility were improved [PTD 1: (0.80±0.05)kg vs (0.56±0.04) kg, PTD 3: (1.06±0.05) kg vs (0.47±0.03) kg, PTD 7: (1.24±0.10) kg vs (0.39±0.07) kg, all P<0.05; PTD 1: (2.05±0.54) vs (1.86±0.72), PTD 3: (2.19±0.61) vs (1.74±0.40), PTD 7: (2.46±0.62) vs (1.53±0.85), all P<0.05; PTD 1: (2.39±0.42) N/cm 2vs (1.91±0.25) N/cm 2, PTD 3: (2.57±0.62) N/cm 2vs (1.72±0.50) N/cm 2, PTD 7: (2.77±0.55) N/cm 2vs (1.54±0.33) N/cm 2, all P<0.05]. The expression of Cyt c and caspase-3 were decreased while the expression of RyR1 and p-mTORC1 were increased gradually in the EDP+VC group ( P<0.05). Conclusions:External diaphragm pacer plays a protective role in ventilator-induced diaphragm dysfunction, which can inhibit mitochondrial damage, reduce oxidative damage, and mitigate diaphragmatic atrophy and injury.
ABSTRACT
Objective To investigate the influences of different mechanical ventilation modes on ventilator?induced diaphragm dysfunction (VIDD). Methods The patients received invasive mechanical ventilation in our ICU after lower abdomen surgery were enrolled into 3 groups according to different ventilation modes. The data of the 3 groups were analyzed. According to the offline results, patients were divided into two groups, the success of weaning as the dependent variable, the clinical indicators with statistical significance as the independent variable, the Logistic regression analysis was performed to analyze the ventilator weaning. Results The mechanical ventilation time, 48 h reintubation rate and the length of ICU stay in the A/C mode group were significantly higher than those in the SIMV mode group and the PSV mode group. The weaning success rate in the A/C mode group was significantly lower than that in the SIMV mode group and the PSV mode group, with significant difference (P<0.05). Weaning success group and weaning failure group had significant differences in the proportion of three ventilation modes (P < 0.05). With weaning as dependent variable, APACHE Ⅱ score, ALB and ventilation mode as independent variables, logistic regression analysis was performed using the enter method. APACHE Ⅱ and ventilation mode were independent influencing factors for weaning. Conclusion Compared with the A/C mode, the SIMV mode and the PSV mode have less influence on VIDD and high weaning success rate in the mechanical ventilation process of patients post?lower abdomen surgery. No significant difference was found between the SIMV mode and the PSV mode in their influence on weaning.